Manufacture of chains.



UNITED srnrns FATE WINFIELD S. POTTER, OF NEW YD'R'K, N. Y., ASSIGNOR T0ALLOY STEEL FORGING': COMPANY, OF WIIMINGTON, IDELAVVARE, A CORPORATIQNOF DELAWAILE.

MANUFACTURE or creams.

No Drawing.

Specification 6r Letters Eatent.

Patented Feb. 2t), 1912.

Application filed December 16, 1911. Serial No.- 666,235.

the following to be afull, clear, and exact description of theinvention, such. as will enable others skilled in the art to which itappertains to make and'use the same.

My'invention relates to the manufacture of chains as,-for'instance,chains'consisting of the ordinary interldcked round sect-ion oval links.

It has for its object the production of a chain of manganese steel.whose links have throughout a strength and capacity to resist shocksand strains substantially equal to the metal in the original unbrokenbar or shape from which the links are formed.

It also relates, generally, to the welding of manganese steel.

It is particularly the purpose and object of my invention to avoid theseparations, segregations, and irregular or coarse recrystallizations,with their consequent weaken-v ing of and injury to the high carbonmanganese steel suitable for the purpose, which" occur when a wroughtbar or other blank shape of such steel is reheated to a high temperature, after the original forming of said bar or blank shape, duringthe welding operation. i p

' In the practice of my invention, the-rod or other blank shape fromwhich the chain is to be formed (hereinafter referred to as the bar), issuitably produced by heating a manganese steel billet preferably toabout 117 5 C. to 1200 (3., rolling the billet to the section of linkintended, and completing the working of the metal during the forming ofthe bar at a finishing heat below 1075 C.

If, after leaving the finishing pass of the mill the bars areto beair-cooled before the next succeeding step of the operation, the

finishing heat of rolling ,should be in the neighborhood of 1075" G. forsmall bars which cool quickly in the air, andproportionately less forlarge bars, as, for-example, the temperature in the last pass of therolls should be about 800 C. to 950 C. for bars of 2 inches thickness. Abar of any required size for chain-making may be finished attemperatures between 800 and IOT5 0.,

. with goodresults, it immediately quenched in water. With thin bars,the cutting andforming-into open links prior to the welding operationmay sometimes be done. cold, but it will usually be found more suitableto bring the links to form by cutting the. bar into pieces, bending andinterlocking the pieces of the "intended chain at tempera tures between350C. and 1025 C., according to the size of the bar. That is to say, at

the time of its conversion into chain, the rolled bar should preferablyhave a temperature within the {range of 350 C. to 1025 (1, andusually 975 C. or closely approximating that temperature. It is then delivered toand speedily passed through-the bar cutting, linlcforming andlink-interlocking mechanism.

The rolled bar may be supplied to the chain-forming mechanism, hot fromthe heat of forming, or after-having been reheated to the appropriatetemperature. To maintain the temperature of 'the rolled bar after itleaves the forming rolls, it may be introduced as it issues from theforming rolls into a hot furnace compartment, or other heater, having atthe time of entry of the hot rolled bar a temperature preferably ofabout 975 C. Or, if the bar has been permitted to cool and requiresreheating, it is restored to substantially the same temper ature withwhich it left the rolls, by rapidly reheating it, thatis to say, byreheatmg it during a time too short to permit the metal to recrystallizein any ob ectionable way. In any event, the bar is subjected to thecutting, linlnforming and link-interlocking action of the chain-formingmecha nism and otherwise prepared for welding, and, as hereinbeforeindicated is supplied to the chaimforming mechanism, eithercold, or hotfrom the heat of forming, or after it has been cooled and subsequentlyreheated.

The welding may be accomplished. by causing an electric current to flowbetween the surfaces to be welded while these surfaces are forciblypressed together. The pressure applied at the Weldis. continued afterthe metal has been caused to flow and after the desired weld has beenproduced, in order to compensate for the weakening tendency of the hightemperatures incident to the welding operation at or in the neighborhoodof the weld. This continued appli-' cation of. force and pressure tendsto sun tliiii press and a'void the and undesirable metal udyoinin the wel the portions or t c link highly heated dun ing the welding ope tionwill be brought.

la to a condensed LU-(l a very fine-grained condition throughout.bonsequently, as the welded chain issues .iflOllltllG forging or pro mg;mechanism, it consists of links which fully rctain throughout theirentire h, i ludii the weld, all of the useful ects of the andcompression produced by the rolls in forming the billet into the rolled.l fact, at the surfaces where the links ha e been welded the metal isei'en still further compressed and improved by the force and pressureapplied during; the forging operation.

To illustrate typical instance of the practice ct thv invention, it willbe assumed that the metal to be formed into a chain is manganese steelhaving in its composition carbon approximately 1.20 per cent., manganese12 per cent. A billet of this metal is heated to about 1175 C).throughout and is rolled, for example, to a round-bar of the di 'ucteror the section of a link of the intended chain. The bar is caused toissue from the rolls a temperature between 000 C. and 1075 C.(preferably 975 C.) is thereupon quickly introduced into the ei-whichwill hare about the same length ,bur and wherein about the same temturewill be maintained. In order to avoid material loss of heat by the barany change in the condition or structure of its steel, the is thendelivered from the heater and through the chainforming and weldijmechanism in such manner that. the c ing oil into link-lengths, theforming, of the links, the welding or" the links, the forging ot thewelded bortions and the final issuance of the welded chain from thechain-formingand welding mechanism is accomplished rapidly so that thecompleted chain has as nearly as possible the same tcmperatiue that thebar has on leaving the rolls. Local inequalities or une enness in thetemperature of the finished chain maybe compensated and equalized by ashort heatingoperation at about 3300 C. to l0l'5 The chain is thenquickly cooled by immersion in water, or the finished. chain may beotherwise rapidly cooled to a temperature below 420 (l. Or, after welding and pressing the links, they may be reheated to about 075 1). to1025 0., reworked at the welds, and then quenched or otherwise ra iiidlycooled.

in order to avoid the occlusion of slag or other foreign matter in theweld, the cuttins: of the bar into lengths is preferably so executedthat the surfaces which are to meet and by their 'tlow form the centralportion of the intended weld project beyond the remainder of thesurtacesto be welded; so that, when the welding heat and the pressure isapplied, the weld occurs first at the center and then progressivelyoutwardly toward. the edges until the weld. is complete.

What I claim is:

1. T he method 01 producing wrought manganese steel chain, whichconsists in cutting a bar of manganese steel into pieces suitable forlinks; bending and interlocking the pieces and. electrically weldingtheir ends to form links; thoroughly working the welded portions attemperatures below 1075 (3.; heating the links to about 1000 (3.; andrapidly cooling to below 420 6.; substantially as described.

2. 'lhe method of producing wrought manganese steel chain, whichconsists in heating a bar of manganese steel to between 350 C. and 1075(1.; cutting the bar into pieces suitable for links; bendingandinterlocking the pieces and electrically welding their ends to formlinks; thoroughly working the welded portions at temperatures be low1075 C.; heating the links to about 1000 C.; and rapidly cooling tobelow 420 C." substantially as described.

3. The method of producing wrought manganese steel chain, which consistsin heating a bar of manganese steel to between 350 C. and 1075 0.;cutting t-hcbar into pieces suitable for links; forming and interlocking the pieces and electrically welding their ends to form links;thoroughly working the welded portions at temperatures between 800 C.and 1075 0.; heating the links to about 1000 C; and rapidly cooling tobelow 420 (1; substantially as described. l. The method of producingwrought manganese steel chain, which consists in heating a manganesesteel billet to about 11 75 (l; rolling the billet to bar form with afinishing temperature below 1075 (1.; cutting the bar into pieces whilestill hot from the heat of rolling; bending and interlockingthe piecesand electrically welding their ends to form links; thoroughly workingthe welds at temperatures between 800 C. and 1075 (1.; equalizing thetemperatures in the links at about 1000 (1.; and rapidly cooling; tobelow 420 0.; substantially as described.

5.-The method of welding, working and heating manganese steel, whichcomprises bringing the ends to be welded to a welding heat; pressing thesaid ends together; thoroughly working the peratures below 1075 G; andrapidly cooling to below 4:20" C.; substantially as described.

welded portions at temv 6. In the production of wrought manganese steelchain, the method of welding, working and heat-treating the links, whichcomprises bringing the ends to be welded to a welding heat; pressing thesaid ends together; thoroughly working the welded portions attemperatures below 1075 0.;

and rapidly cooling to below 420 0.; sub 'stantially as described.

7. In the production of wrought manga- 'nese steel'chain, the method ofwelding, working and heattreating the links, which comprises bringingthe ends to be welded to a welding heat; pressing the said endstogether; thoroughly working the welded portions at temperatures below107 5 0.; equal izing the temperature in the welded and worked linksbetween 800 0. and 107 5 0.; and rapidlycoolin to below 420 0.;substantially as descri ed.

8. In the production of wrought manganese steel chain, the method ofwelding, working, and heat-treating the links, which comprises bringingthe ends to be welded to a welding heat by the passage of an electriccurrent; pressing the said ends together-i,

thoroughly working the welded portions at temperatures below. 1075"- 0.;heating the Welded and worked links to about 1000 0.;

and rapidly cooling'to below 420 0.; subforming the links; bringing theends to be welded to a welding heat; pressing the said ends together andthereby welding them; thoroughly working the welded portions attemperatures below 1075 0.; and finally cooling the metal rapidly fromabout 1000 0. to below i20 0.; substantially as de scribed.

In testimony whereof I aflix my signature,

in presence of .two witnesses.

WINFIELD S. POTTER. Witnesses;

M. A. BILL, JOHN 0. 'PENNIE.

Copies of this patent may be obtained for five'cents each, by addressingthe Commissioner of Patents,

Washington, D. G. v

